


Halloween Party Time

by Sivan325, SivanShemesh (Sivan325)



Series: Shadowhunters Bingo 2020-2021 [2]
Category: Shadowhunters (TV), The Mortal Instruments Series - Cassandra Clare
Genre: Halloween, Halloween Costumes, Humor, Implied Sexual Content, Inspired by Buffy the Vampire Slayer (TV), Knifeplay, M/M, Oblivious Alec Lightwood, Shadowhunter Magnus Bane, alternative universe, bingo square: shadowhunter! magnus
Language: English
Status: Completed
Published: 2020-11-02
Updated: 2020-11-02
Packaged: 2021-03-09 07:33:22
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,617
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/27347428
Author URL: https://archiveofourown.org/users/Sivan325/pseuds/Sivan325, https://archiveofourown.org/users/Sivan325/pseuds/SivanShemesh
Summary: Arranging a costume party for Halloween should not be that hard, right? What could go wrong?
Relationships: Magnus Bane/Alec Lightwood
Series: Shadowhunters Bingo 2020-2021 [2]
Series URL: https://archiveofourown.org/series/1956103
Kudos: 14
Collections: SHBingo 20-21





	Halloween Party Time

**Author's Note:**

> Thanks to Jessa to beta-read this, you are an 😇  
> All the remain mistakes are mine.
> 
> \--
> 
> Written for Shadowhunters Bingo - Square: **Shadowhunter!Magnus**
> 
> \--
> 
> Disclaimer: The fabulous work belongs to Cassandra Clare, thank you for creating the Shadow world.

Oct. 31, at night

Jace thought it would be best if his brother changed his clothes and became someone else at night. And since his parabatai hated Halloween, maybe it was time to change.

Jace would not admit to his brother that he gave Magnus full shadowhunter gear and all fit to his size.

Not knowing why his brother did not love Halloween, Jace and Izzy played along to bring Alec a special costume. They would paint his body green. Alec would not be pleased. But they were going to have the time of their lives, it was time to party.

Alec sat in his room. He already wore his costume as Izzy painted his exposed body with green and other elements.

“Where did Jace found this awful stuff?” Alec asked his sister.

“I think that it’s Clary who pointed it out. After all, she knows mundane shops,” Izzy replied and added a warning, “Alec, don’t move, you’ll ruin it. And don’t scratch this.”

“It’s itchy,” Alec complained.

“Don’t touch it. I swear that I will use the Quietude rune on you,” Izzy warned him.

“You wouldn’t dare.” Alec looked at her.

“If you won’t stop moving maybe I will do that. Now, let me finish with it and we’ll be off.” Izzy glared at her brother as she added, “I’m dying to see what Jace, Clary, Simon and Magnus costumes are like for Halloween.”

“Probably no worse than whatever you’ve made me look like,” Alec complained as he sighed heavily.

“Probably. Now _hush_ big brother, let me finish with you and then we will be off.” Isabelle told him as he tried not to do anything, even though it itched him.

After several minutes and lots of glaring from Izzy to Alec, Izzy was done. She looked at him with a large smile on her face.

“Now you are ready for the party, big brother.”

“What am I supposed to be, anyway?” Alec asked as he walked over to the door.

“I don’t know, I forgot to ask Simon. All he gave me was a photo for your character costume,” Izzy replied.

“What is your costume?” Alec asked, not seeming pleased with her answer.

“I don’t know. But if we arrive at Magnus’ loft in time, Clary could paint me and I her, so come on big brother.” Izzy urged him toward the door and outside of the Institute.

Izzy led him away. She was the only one that was armed. Izzy wouldn’t let his character carry any weapon on him. It would ruin her body painting, something that she didn’t want to happen as they hurried toward Magnus’ loft.

When they finally arrived at the loft, Izzy knocked on the door and Jace opened it. She looked at Magnus with awe as she and Alec stepped inside and the door was closed after them.

“Mags, you look beautiful. Never knew how hot you’d look in Shadowhunter gear. The black suits you, love,” Alec told him when he saw him.

“Thank you, darling,” Magnus blushed at the compliment and added, “But what is that costume?”

“I have no idea, I put my trust in Izzy. I have no idea what I am in this game of yours,” Alec replied.

“You are-” Simon started to say as he emerged from the other room, covered in magic dust. Alec could not tell what it really was.

“Shush, now, Simon,” Jace requested as he walked with Clary, and added, “Just don’t be silly.”

“But he is silly,” Alec told him with a smile.

“Jace, Alec, shut up, both of you. Simon is a Seelie. _Fae_ if you will. But he is not dumb or silly in that way,” Izzy told her brothers as she motioned toward her boyfriend.

“I see you are already dressed up with your costume, I better wear mine. Clary, come and help me,” Isabelle told them and walked to the dressing room with Clary.

“What are yours and Clary’s?” Alec asked, trying not to touch the fabric. It caused him to itch.

“I’m a jester, like the clown in fairy tales, and Clary is a sexy maid,” Jace replied.

Alec touched his boyfriend’s hand as he traced the runes all over him.

“It looks so real, Mags,” Alec told him.

“Right? Clary did a spectacular job, and Jace even gave me your stele.” Magnus grinned at his boyfriend.

“My stele?” Alec asked, curious.

“Of course. Unless you mean for something else.” Magnus smiled at him.

“No… it’s fine. Since I still don’t know what I’m meant to be in the first place,” Alec muttered.

“So, what’s Izzy then?” Alec asked, still curious.

“Wait and see, darling,” Magnus replied as he walked near his boyfriend and attempted to kiss him. Only to be stopped at that moment by Izzy calling outas she came from the other room. Clary was behind her.

“Are they fangs, Iz?” Alec asked.

“You really did it for me?” Simon said in disbelief as he came closer to kiss her on the cheek.

“Of course.” Izzy winked at him.

“What am I missing here?” Alec asked.

“You did not tell him?” Simon smiled as he pulled out his phone to take a picture of his friends; he now had blackmail material to use in the future.

As Izzy, Clary, Simon and Jace left the loft, happy with each other, Magnus and Alec, who remained inside, did not hear the spell that was cast on them. Iris had come to collect her revenge and Halloween made for a great opportunity for her to do so.

Magnus removed his sword from his thigh holster and aimed it toward Alec who seemed frightened, and could only mumble, “Arrr…”

“I’m getting you into a cell. You are a monster.” Magnus threatened the green creature. The blade was close to Alec’s neck.

Izzy walked back inside, not knowing why Alec and Magnus had not yet joined them. What she saw made her so furious that she did not notice the blonde cat disappearing outside.

“What are you doing? It’s not time to play, we are going to dance,” Izzy told them.

“I’m going to take you and that creature toward the cell in the City of Bones.” Magnus told her, bringing the seraph blade closer to her brother’s neck.

“Why are you standing there like a tall tree? Do something, Alec!” Izzy told her brother, who looked back strangely at her.

Izzy pulled out her phone and called Jace to tell him the recent news, and that she would probably need a reinforcement; that there was something wrong.

The trio hurried inside to see Magnus aiming his sword toward his boyfriend, who was just staring at him with a scary face. Izzy tried to remove the fake fangs to show them to Magnus.

“What is going on in here?” Clary asked.

“See what I caught? A monster and a vampire. Guess who will take a reward tonight?” Magnus grinned at them.

“Magnus, this is your boyfriend, Alec,” Jace tried to tell him, but the Shadowhunter Magnus was far from listening as Isabelle hurried toward the dressing room with Clary at her heels.

Simon sighed, not believing what he was seeing. He knew that there was not going to be a party tonight. Something was certainly affecting Magnus and Alec. They were not acting like themselves.

Magnus was alerted as Izzy returned with Clary. They both had the same gear as him. Jace was still watching as he left them to change himself; he thought that his Parabatai would need all the help he could get.

At least Magnus had got himself a monster; a tall monster that he could lock in one of those cells and then go and hang out with his friends.

“Come on, let us put him in the cell and then go celebrate,” Magnus urged his fellow Shadowhunters. Then he added, to Simon, “I’m not sure that you can follow us inside but you can wait outside, Seelie Simon.”

Simon only nodded, not knowing why Alec wouldn’t hold his boyfriend to account about a comment like that. There was no way that this was any kind of spell. They did not see any warlock inside the loft. But hadn’t they seen a cat leaving the loft? Did the cat have something to do with it?

Simon was certain that his mind was playing with his imagination. He knew from Clary that Iris was locked in Idris. But what if...?

“Jace, wait a minute,” Simon blurted out.

“What is it?” Jace asked as he spared another look toward the horrified Parabatai of his.

“I think that there is something wrong with your brother and Magnus,” Simon replied.

“We all know that, especially as we did not tell Alec what his costume is in the first place,” Jace told him and added, “The only reason for them to act like this is magic. But we don’t know who cast the spell. So we don’t know who can release them from it.”

“I saw a cat. A blonde cat. I think that Izzy saw it too,” Simon told him as he remembered the cat.

“I guess that we need all the help we can get,” Jace admitted, and then he said to his sister, “I will call Catarina. Maybe she could help us here. We need to find Iris, hopefully it will be her.”

“I’ll watch our brother and Magnus,” Izzy answered back as she and Clary followed the eager Shadowhunter, who was preparing totake his prey over to the Institute. She added to Clary, “I never thought that I would say it but Magnus make one hell of a Shadowhunter.”

“Right? And he looks so hot with this gear,” Clary agreed and laugh.

“I never thought to picture him as a Shadowhunter, and my brother is the freak monster, as Magnus calls him,” Izzy told her as they followed the eager Shadowhunter through the streets, taking his golden prize with him; the Head of the Institute, wearing a weird costume. “I guess that it’s time to reveal what costume my brother wears, since he’s acting like it.”

“Oh, right. He is Frankenstein,” Clary revealed, only to see her friend with a shocked face.

“By the angel, what is that name? Is that a demon?” Izzy asked her, not knowing what it was.

“Long story short is that Frankenstein was created by a scientist who created him in a castle at night,” Clary replied.

“Oh… OH… By the angel, this is not good.” Izzy said, watching her helpless brother with a sword to his neck, not knowing what was happening to him. She was certain that he did not know what he was in the first place.

“Let’s hope that the boys will figure a way to get themselves back to normal,” Clary told her.

“Yeah, in the meantime, let’s hope that Magnus will not harm his boyfriend too much. And hopefully, when it’s over, let us hope that Alec will not ban parties because of this,” Izzy added with hope in her eyes.

They were getting closer to the Institute and they could see Raphael standing near the door as Catarina and Ragnor stood by, watching the scene with surprised looks on their faces.

“Is that Magnus?” Raphael asked.

“Why would he take Alec as a hostage?” Catarina asked, looking shocked.

“I better use that as blackmail for the future, then.” Ragnor snapped a shot; now he had living proof of Magnus as a Shadowhunter.

When Magnus was near the door, he saw three Downworlders. He requested from them, “Move!”

When they did not move, he turned toward one of the girls and asked them for help. “Take them with you.”

As Magnus entered the Institute, Izzy simply told them, “Magnus is not himself. Do you think that there is a spell involved?”

“Simon is right, magic seems involved here. It’s dark magic.” Ragnor said.

Raphael turned to look at him. “How can you tell he is not just acting?”

“Raphael, do you ever see Magnus playing with swords? He is the worst,” Ragnor replied to Raphael and added, “I remember that time in Peru, Magnus tried to be a pirate, and let’s just say Magnus and swords don’t play along. And to see him with a sword, holding it very close to his boyfriend, I can say that he is enchanted.”

“Are there more warlocks that deal with dark magic?” Clary asked.

“Who wants to take revenge on Magnus anyway? Iris is locked in Idris, right?” Catarina checked.

“I guess that it is time to check. I’d better let Jace know and we will leave at once,” Clary replied to her.

“I’m already here, Clary,” Jace said with a grin as she startled.

“Jace, don’t spook me,” Clary warned him.

“Jace, don’t change at all,” Izzy mumbled at him as she followed Magnus into the Institute.

“Time to save big brother mission.” Jace laughed and joined Clary as she opened a portal with a rune.

“Let’s hope that my navigation is approved since last time,” Clary told him.

They stepped through the portal to Idris while Magnus, with the help of Izzy, put Alec in the cell below instead of in the City of Bones. Izzy did not wish for the Inquisitor to learn of this; it was the last thing that they needed right now.

The Shadowhunters in the Institute were wondering why the Head of the Institute was in the cell and why Magnus, the so-called warlock, was acting like he truly was a Shadowhunter.

“No one is doing anything about it, it’s a Halloween thing. Hopefully everything will be back to normal soon, just enjoy the moment. I don’t think that we will see it again. Don’t even send Magnus’ report ahead. It won’t do us any good favors,” Izzy told them as she stepped into the ops.

In Idris, Jace and Clary met with the consul, Jia, which they tried to avoid but to no avail. So they continued to talk business and she asked about how Alec was doing.

“Alec is fine. We are here to ask if the warlock Iris might have broken out from her cell?” Clary asked her.

Jia did not know if they were joking but she looked at them and noticed how serious they were. “Follow me. There is only one way to find out.”

They followed her toward the cells where the guards were watching the Downworlder in question.

“Did she leave her cell?” Jia asked one of the guards.

“No, I watched all the time,” The guard replied and the other guard nodded that he saw her there too.

“Thank you, I guess,” Jace said as they both left the premises.

When they were outside, Jace looked at Clary, hoping that they would not make any more mistakes. After all, Iris was not involved. The guards told them. And Jia looked at them like they were hiding something.

“I guess that we will have to wait until the morning,” Clary accepted as she opened the portal.

As they left the portal, they found their friends in the alley next to the Institute and updated them about Iris.

“Did you check the security tapes? Did Iris’ magic even work at Idris?” Simon asked. He looked worried.

“If we go back to Idris, Jia will suspect and come to visit us. We can’t risk it,” Jace replied to him.

“What should we do?” Catarina asked.

“Let us sleep the night and hopefully everything will be back to normal soon. We can only hope,” Clary replied as she looked at the group of her friends.

“Just keep on updating us about it.” Raphael requested.

“Don’t worry, Raphael. I’m sure that if everything goes back to normal, we will hear from Magnus himself.” Ragnor smiled.

Magnus rested his head on the bed, trying to sleep, but all he could think of were that there were demons to hunt and maybe he had missed more on the way; since Halloween was luring lots of demons. He felt so tired even though he wanted to hunt more. He closed his eyes and slept.

The creature in the cell below knocked his hands on the transparent glass that surrounded his cell. And when he could feel nothing, since sleep did not come easy to him, he leaned against the wall and just looked hopeful that someone would hear him.

* * *

Nov. 1 in the morning

Magnus woke up in a familiar room. He still wore the Shadowhunter gear. He wondered why he was in Alexander’s room and what they did last night and where is his boyfriend?

He left the room with lots of questions, seeking either Izzy or the blond shadowhunter.

“Good morning, Magnus, how do you feel today?” Izzy asked him with a smile.

“Do you want to hunt some demons?” Clary asked him.

“What happened last night? I have a horrible headache,” Magnus admitted, holding his head.

“You don’t remember?” Jace asked and then he added, “Can you do magic?”

Magnus looked at him like the Shadowhunter had lost his mind or something. He moved his hands as sparkles appeared from them. “Of course I can do magic, I’m a warlock.”

“Right,” Jace mocked him and added in a whisper, “I saw how you acted like a true Shadowhunter. Catching a monster and leading him to the Institute.”

“I heard that. And what do you mean that I _act_ _ed_ _like a_ _S_ _hadowhunter_?” Magnus asked as he conjured a drink and drank it to soothe his pain.

“I should let Ragnor and Catarina know about it. They will be delighted with the news.” Izzy grinned at the baffled warlock.

“I can do better. I think that I will go back to the loft. I need a good sleep,” Magnus told them and noticed that his boyfriend was not with them as he stopped.

“Wait, where is your brother?” Magnus asked.

“You mean the monster that you locked in the cell downstairs?” Jace asked. He turned to look at Izzy. “We need to hurry, he will kill us...”

They could hear their brother’s shouts as they came down with Magnus on their tails.

“Alexander, I never thought that I would see you in that dreadful cell,” Magnus told him while Jace released him.

The paint, the green paint, was still there. “Come along, Frankenstein. You are coming with me to the loft. My magic will deal with it,” Magnus told Alec and grabbed him.

“Frankenstein? What are you talking about? My head hurts. What did we do last night?” Alec asked as one hand gripped the transparent glass, trying to keep his body steady.

“You don’t remember?” Jace asked.

“What is the last thing that you two do remember?” Clary asked.

“I was about to kiss him, and then nothing, why?” Magnus asked, as Alec confirmed his boyfriend’s words.

“Do you want the good news or the bad news first?” Izzy asked, smiling at them.

“Bad news,” Alec replied while his boyfriend wanted to know the good news.

“For the bad news, we think that whoever cast the spell on you that turned you into your costumes last night is guarded at Idris and never left,” Clary replied. And Jace added, “For the good news, we have pictures of you. I mean, Simon and Ragnor took some. I don’t know if there is also a video edition of your acting last night...”

“Come on, darling, let’s go to sleep at home. My head is killing me,” Magnus admitted to his boyfriend as he opened a portal and they walked through.

The first thing they did was go to bed. The magic would clear the paint later from Alec; it could wait.

Jace texted Ragnor that everything was under control, but they needed proof.

Later that day, when Magnus and Alec were starting to feel better, Magnus left the bedroom to shower and Alec went to the kitchen to fetch himself something cold to drink.

Before he opened the fridge, he noticed pictures on it, of himself and Magnus. But Magnus had a sword held to his neck?

“Mags, you need to get over here, now!”

Magnus left the shower, only a towel covering his waist. “What is it, Alexander? Oh, I forgot to remove that paint from you. You look like Ragnor now.”

“Do you remember any of this?” Alec asked as he pointed to the pictures.

“No, not at all.”

“Why did we dress like that anyway?” Alec asked.

“We were about to go out for a Halloween party, I think.” Magnus replied.

Magnus’ towel landed on the floor and Magnus used his magic to remove the green paint from both Alec and his clothes.

“I hate Halloween,” Alec told him.

“I know, darling, I’m sure that everyone knows that.”

“But Mags, I _really_ hate Halloween. This mundane holiday is nothing but trouble,” Alec ranted at his boyfriend.

Magnus took one of the pictures off the fridge and showed it off to his boyfriend. “But look how hot and handsome I am with this Shadowhunter gear on? Don’t I look hot in the thigh holster?”

“Magnus, don’t change the subject.” Alec kissed him and added, “I really, really, _really_ hate Halloween.”

“Darling, I know that.” Magnus kissed him back, moving him toward the bedroom again as he repeated the question, “Don’t I look smoking hot?”

Alec looked at the picture and smiled at him. “Very hot. Can you not feel me?”

Magnus did feel him. He could feel the bulge from his boyfriend and shoved him onto the bed.

“Maybe I should wear it every Halloween…” Magnus suggested with a grin on his face.

**The End!!!**


End file.
